1. Field of the Invention
The present invention relates to a light source apparatus and a projection display apparatus provided with a plurality of light sources that emit light having a wide spread angle at a fast axis and a narrow spread angle at a slow axis.
2. Description of the Related Art
Conventionally, there has been known a light source (for example, LD: Laser Diode) that emits light having two axes (a fast axis and a slow axis). The light emitted from the light source has a wide spread angle at the fast axis and a narrow spread angle at the slow axis.
Further, it has been proposed to increase, by arranging the light sources in an array form, the amount of light emitted from a light source apparatus provided with a plurality of light sources. For example, in a light source apparatus, a plurality of light sources are arranged along a slow axis (for example, Japanese Unexamined Patent Application Publication No. 2006-337923).
However, in the aforementioned technology, etendue is not considered. Specifically, etendues at the slow axis is larger than etendue at the fast axis. As described above, when imbalance of the etendues at the two axes occurs, it becomes necessary to design an optical system provided at a rear stage of the light source in accordance with the size in an axial direction in which the etendue is larger. Therefore, an optical system with a small F number is required, resulting in an increase in the size of a lens or cost.